Slotting machine



Sept. 15, 1931. H. E. FRENTZEL 1 1,823,857

SLOTTING MACHINE Filed Feb. 27, 1926 3 Sheets-Sheet 1 E5 INVENTOR flmw/rffkmrza.

BYW/MD.

ATTORN EY Sept. 15, 1931. E. FRENTZEL 1,323,357

SLOTTING MACHINE 7 Filed Feb. 27, 1926 s Sheets-Sheet 2 ATTORNEY INVE R b27471? mvrza.

Patented Sept. 15, 1931 UNITED STATES PATENT orrics HERMAN E. FRENTZEL, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO II-IE FALK CORPO- RATION, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN snotrcrme MACHINE Application filed February 27, 1926. Serial No. 91,019.

This invention relates to slotting machines.

One general aim of the present invention is the provision of a machine for cutting slots with non-parallel walls.

The patent to James Bibby, No. 1,391,713, issuedSept. 27, 1921, describes a resilient coupling embodying a pair of coupling disks each having a peripheral series oflongitudinally flared slots. The side walls of each slot are longitudinally curved, the degree of curvature depending upon the size of the coupling and the degree and character of the load for which it is designed.

A more specific object o f-the present invention is the provisionof a machine capable of accurately cutting slots of that form with side walls of definite longitudinal curve.

Another object is the provision in a slotting machine or the like of improved means for effecting a cutting feed and for indexing the work in properly timed relation.

Another object is the provision of means for absolutely preventing operation of the feed mechanism until the indexing has been completed. v I

Other objects and advantages will appear from the following description of an illustrative embodiment of the present invention.

In the drawings Figure 1 is a transverse sectional view of a slotting machine constructed in accordance with the present invention. This view is taken substantially along the line. 1-1 of 7 Figures 2, 3 and 4.

Figure 2 is a plan view partly in section.

Figure 3 is an elevation of the left side of the machine with parts broken away along the section line 33 of Figures 1 and 2. i

Figure 4 is a sectional View taken substantially along the line 44 of Figure 2. 1

Figures 5 and 6 are sectional views of a trip mechanism shown in Figure 1.

Figure 7 is a sectional view of the trip mechanism taken at right angles to the sectional plane of Figures 5 and 6.

Figure 8 is a detail of a clutch and control mechanism.

Figure 9 is a fragmentary perspective view of coupling disk having peripheral slots formed by this machine.

Figure 10 is a diagrammatic view illustrating the action of the cutters in producing theslots. I

The machine selected for illustration isdesigned to cut a series of longitudinally flared slots a in the periphery Z) of a coupling disk 0. From an inspection of Figures 9 and 10 it will be noted that the opposite side walls a? and d of each slot are oppositely curved longitudinally. Each slot is formed by a 'pair'of Cutters 6 and e reciprocating substantially 1n unison between the full hne positions and the dotted line positions, re-

spectively, of Figure 10. Cutter 6 follows the curved path indicated by the line f and cutter 6 follows the curved path indicated by the line 7". As the cutters move toward the left from the full line positions cutter e is'on an idle stroke and cutter 6 produces a cut across the periphery of the disk forming the wall 01. As the cutters move toward the right fromthedotted line positions, cutter e is idling and cutter e is producing a cut across the periphery of the disk, forming the wall d. Both cutters serve to form the base of the slot, each acting on a portion thereof, the cutting path of each overlapping with that of theother to thereby complete the same.

The machine shown in Figures 1 to 4 comprises a main frame 10 in the form of a hollow casting of generally rectangular shape, having two tables 11 and 12 formed thereon. A housing 13-mounted for adjustment in ways 14 on the table 11, carries an arbor 15 for receiving and supporting the coupling disk c, the disk 0 being clamped thereon between a flange 16 and nut and washer 17. The arbor 15 is fixed to a shaft 18, journalled in the housing 13 and controlledby a Worm wheel 19 fixed to the shaft,

andenclosed within a gear casing 20, carried by the housing. The worm wheel is operated intermittently, to index the work, by a worm 21, driven by mechanism to be hereinafter described. The machinemay be ac- J commodated to operate on disks of various diameters by adjusting the housing 13 along the ways 14.

The table 12 constitutes a support for a main feed carriage 22, mounted for travel toward and from the work along a way 23 formed centrally within the top of the table 12. The carriage 22 is actuated and con trolled by an upright lever 24 disposed within the main frame 10, and rockably mounted upon a horizontal pivot pin 25, fixed between a pair of ears 26 depending from the table 12. The upper end 27 of the lever is rockably engaged within an appropriate fork 28 depending from asquare nut 29, threaded to receive a screw 30, horizontally disposed within a groove 31, formed in the top of the table 12 below the way 23. The screw is j ournalledat one end in an extension bracket 32formed as an integral part of the carriage 22. The nut 29 is restrained against rotation by contact with, the bottom of the carriage 22. This arrangement of partspermits a ready adjustment of the carriage 22 relative to the lever 24, by turning the screw,

so that the carriage may be advanced or retarded to effect adjustment thereof relative to the work.

The lever24 is actuated and controlled by a feed cam 33, on a shaft'34, journalled in an appropriate housing 35, fixed in the main frame 10. The lower end of the lever 24 carries a shoe 36, maintained against the cam 33 under the pressure of a spring loaded plunger 37 mounted within an appropriate housing 38 fixed in themain frame. The plunger 37 is connected to the lever 24, through a link 39, and is connected through a stem 40 with a piston 41 closely fitted within a bore 42 formed in the housing 38. The cam 33 is driven slowly in a counter-clockwise direction (Fig. 4) by mechanism to be hereinafter described, and is so shaped as to cause the lever 24 to rock clockwise at a uniform rate during each complete rotation, thus causing the carriage 22 to advance toward the work at a uniform rate. 7

When the shoe 36 passes overthe shoulder 43 on the cam the lever 24 is rockedquickly in a counter-clockwise direction, under the pressure of the spring loaded plunger 37, thereby causing a quick return stroke of the carriage. This return movement of the carriage and lever is cushioned'and somewhat retarded by the piston 41, which is checked in its movement by the body of air within the bore 42, in a manner characteristic of a dashpot.

The carriage 22 is provided with two laterally spaced uprights 4444 formed upon the rear portion thereof and housing gears to be hereinafter described. A gearhousing 45 is fixed between and carried by the uprights 4444.

Two separately operated tool carriers 46 slide 5353 is mounted for lengthwise reciprocation in each guide 5151, each slide being provided with an integral extension bracket 54-54, projecting'from the inner end thereof for receiving and supporting the tools 6 and 6', respectively. Each tool slide 5353 is reciprocated continuously by a link 5555, pivotally supported at one end upon a stud 5656 projecting from the tool slide, and at the other end upon a pin 5757, carried by a crank 5858. Crank 58 is mounted upon the end of a horizontal drive shaft '59 journalled in an appropriate casing 60 formed as an integral part of the carrier 46, and crank 58 is mounted upon a similar shaft 59., journalled in a similar casing 60 formed as an integral part of the carrier. 46". Shafts 59 and 59 rotate continuously in the same direction witlrthe cranks 58 and 58' maintained in substantially'the same phase relation. 7

It will be noted, from an inspection of Figure 1 that the two guides 51 and 51, though separately mounted on the carriers 46 and 46, are closely associated and so disposed that the inner end of one constitutes, in effect, a continuation of the other. Guide 51 curves upwardly from its inner end so that tool 6 reciprocates along an upwardly curved path, as indicated by line f of Figure 10 and guide 51 curves downwardly from its inner end, so that tool 6 reciprocates along a downwardly curved path, as indicated bythe line f of Figure 10. The curvature of these paths may of course be modified by replacing the guides and cooperating slides by guides and slides of different curvature. It will also be noted that by mounting the tools in the extension brackets 5454 each tool is carried beyond the inner end of its supporting guide so that the, inner ends of the paths of travel of the two toolsoverlap, each tool passing through the work before it reaches the end of its inward cutting stroke. Thus tool 6, on its inward stroke (toward the right in Figure 1) cuts across the face of the work so as to form the upper side wall of the slot, and tool 6, on its inward stroke toward the left inFigure l) cuts across the face of the work so as to form the lower side wall of the slot, both tools forming the base of the slot. 1

In the machine shown provision is made for alternately advancing the carriers 46 and 46, upon the carriage 22, during the inward cutting stroke of their tools ee, respectively, to permit the tools to engage the work, and for alternately retracting the carriers, upon the carriage 22, during the outward return stroke of their tools, respectively, to permit the tools to clear the work. For this purpose each carrier is provided with a cam'roller 6161 supported between brackets 6262 thereon. These rollers bear against separate cams 63 (one of which is shown in Figure 4) fixed upon opposite ends of a shaft 64, journalled in and projecting through the opposite sides of the gear housing 45 hereinabove mentioned. A spring 65-65 within each carrier 4646 urges the carrier rearwardly so as to retain the roller 61-61 against its cooperating cam. In this instance each spring is connected at its forward end with an eye 66 anchored in the forward wall of the carrier and at its rear end with a rod 67 that extends loosely through the rear wall of the carrier and is anchored as at 68 in one of the uprights 44. The cams 63 are driven in a counter-clockwise direction (Fig. 4) at the same rate as the cranks 5858 and are so timed as to advance and retract the carriers 46-46', alternately, in timed relation with the reciprocationof the tool slides, as above pointed out. 1

The cams 63 and the shafts 59-59 are driven from a shaft 69, journalled in the uprights 4444, and. extending through the gear housing 45. This shaft is driven from a motor 70, disposed in the base of the main frame 10, through a belt 71, trained over a pulley 72 on the motor shaft and a pulley 73 011 the end of the shaft 69. Worms 7474 on this shaft, within the uprights 4444, respectively, mesh with worm wheels 7 5-7 5 fixed to shafts 7 6-7 6, journalled in the uprights and projecting into the casings 6060, carried by the carriers 4646. Shaft 76 is connected in driving relation with crank shaft 59 through a pinion 77 and gear 78, permitting longitudinal reciprocation of the shaft 59, with its carrier, with respect to the shaft 76. A similar drive connection is provided between shafts 76 and crank shaft 59. A pinion 79 on the shaft 69 meshes with a gear 80, constituting one of a train of appropriate speed reduction gears within the gear housing 45, through which the cam shaft 64 is operated.

The motor also drives a horizontal shaft 81, which drives a vertical shaft 82, through a worm and worm wheel within the casing 83. Vertical shaft 82 carries a worm (not shown) which meshes with a worm wheel 84, fixed to a hollow shaft 85, journalled within an appropriate housing 86 .above mentioned, carries a gear 91 connected witha gear 92 on the feed cam shaft 34, through an idle gear 93. An appropriate clutch 94 provides a releasable connection between shafts 89 and 90. Thus when the clutch 94 is closed the feed cam 33 is operated and the feed carriage 22 advanced and retracted in the manner hereinabove described, and when the clutch is opened the cam 33 and carriage come to rest. The clutch is controlled by an upright hand lever 95 in a well known manner.

A shaft 96, projecting from the housing 86 and having one end projecting loosely into the hollow shaft 85, is yieldably driven from the worm wheel 84, through an appropriate slip clutch 97. The clutch shown comprises a ring 98, fixed to the worm wheel 84, and surrounding a disk 99, splined on the shaft 96. A series of spring loaded plungers 100 seated in, and projecting radially from the periphery of the disk 99, bear against the internal surface ofthe ring 98,

and constitute a frictional drive connection I between the ring and disk. The shaft 96 is connected through an appropriate coupling 101 with a stop. cam 102, fixedto a'shaft 103. Shaft 103 is .journalled at opposite ends in gear housings 104 and 105, both carried by the gear casing 20 previously mentioned. A train of change speed gears 106 within the housing 105 establishes a driving connection between shaft 103 and a shaft 107 carrying the worm 21. As previously pointed out the worm 21 constitutes the driving means for the arbor 15.

Rotation of the shaft 103, and consequently the worm 21 and arbor 15, is controlled by mechanism under the control of the main feed carriage 22, so as to effect a predetermined rotation of the work upon each return stroke of the feed carriage. Mechanism for this purpose is illustrated in detail in Figures 5, 6 and 7. A bracket 108, fixed to the side of the housing 104, contains a detent in the formof a plunger 109, reciprocable longitudinally therein. A spring 110 yieldably maintains the plunger 109 in the advanced position of Figure 5 with the tooth 111 on the end thereof in looking engagement with a shoulder 112 on the stop cam 102. In this position the plunger retains the cam 102 and shaft 103 against rotation, the slip clutch 97 permitting this shaft to be so held. The plunger 109 may be retracted, however, into the position shown, by a lever 113, extending therethrough, and rockably supported intermediate its ends upon a pivot pin 114 within the bracket. The lower end of the lever is connected through a link 115 with a piston -116, reciprocable in a bore '117 in the bracket. Fluid pressure supplied through a pipe 118 from an appro-prlate pressure source may be admitted to the bore 117 through passages 119 and 120. A spring loaded valve 121 normally closes communication between pipe 118 and passage 119. The valve is provided with a stem 122 projecting upwardly into the passage 119 in alignr ent with the reduced portion 123 of an actuating stem 124, mounted for vertical reciprocation in the bracket. The actuating stem 124 is normally retained in the upper position, shown in Figure 7 by a spring 125, and in this position the valve 121 is closed. An exhaust port 126 leading from the passage 119 is uncovered when the actuating stem is in this position, so that the bore 117 is normally open to atmosphere. hen the actuating stem is depressed, however, the port 126 is closed thereby and the valve 121 forced into open position, so that fluid pressure is then admitted to the bore 117, and the piston 116 is actuated to rock the lever 113 and force the plunger 109 into the retracted position of Figure 6. This releases the stop cam 102 and permits the shaft 103 to rotate, under the. action of the slip clutch 97.

The actuating stem 124 is actuated and controlled by a trip lever 127,carried by a rock shaft 128, loosely mounted for length wise movement in ears 129 projecting upwardly from the bracket 108. A spring 130 yieldably retains the rock shaft 128 and trip lever in the position shown in Figure 5. The trip lever carries a plate 131, which, when the lever and rock shaft are in this position, lies within the path of movement of a similar plate 132, carried by an arm 133, adjustably fixed to the side of the main feed carriage 22. One end 134 of the rock shaft 128 projects into the path of movement of the upper end 135 of the lever 113, so that when this lever is shifted by the piston 116 into the position of Figure 6, the rock shaft 128 and trip lever 127 are shifted toward the left and the plate 131 carried thereby is shifted out of the path of travel of the plate 132.

r The arrangement is such that during the advance of the main feed carriage 22, the de .nt plunger 109 is in the forward position of Figure 5, the stop cam 102 and shaft 103 is held against rotation, and the indexing mechanism is at rest. Upon each return stroke of the feed carriage 22 (toward the right in Figure 7), the plate 132 carried by arm 133 strikes the plate 131 on the trip lever 127, and rocks the trip lever clockwise, so that the actuating stem 124 is depressed, against the pressure of spring 125, and the lever 113 and plunger 109 are forced into the position of Figure 6. The stop cam 102 is released and the shaft 103 is rotated by the slip clutch 97 so as to operate the indexing mechanism. By this movement of the lever 113, however, the rock shaft 128 and trip lever 127 are shifted laterally, so that plate 131 disengages plate 132, the trip lever is released and the actuating stem 124 permitted to rise under the action of spring 125. The valve 121, thus released, closes, thus freeing the piston 116, lever 113 and plunger 109, permitting the plunger 109 to return against the stop cam 102. The stop cam 102 and shaft 103 continue to rotate, however, through a complete turn, until the shoulder 112 is reengaged with the tooth 111 on the plunger. 7 I

Provision is also made in the machine shown for preventing advance of the feed carriage during the operation of the indexing mechanism. This is accomplished by mechanism shown in Figures 1, 2,3 and 8. This mechanism comprises a cam 134, carried by the shaft 103, and cooperating with a roller 135, carried by the upper end of a plunger 136 mounted for vertical reciprocation in a bracket 137 fixed to the main frame 10. The plunger 136 with its roller-135 is yieldably held upwardly against the cam 134 by a spring 135. The cam 134 is of circular form except for the depression 138 therein. 1 A rock shaft 139 journalled'in an arm 140, on the bracket 137, is actuated and controlled by an arm 141 fixed thereto and operatively engaged with a fork 142 carried by the plunger 136. The rock shaft 139 extends toward the rear of the machine and carries the clutch operating lever 95, hereinabove mentioned, which is fixed thereto. It will be noted that earn 134 and the stop cam 102 are both fixed to shaft 103 so as to rotate in unison.

The arrangement is such that when the shoulder 112 of the stop cam is engaged with the tooth 111 of the detent plunger 109, the depression 138 in cam 134 is in position to receive the roller 135 of plunger 136. Vith the parts in this position the plunger 136 is elevated and the lever 95 is in position to close the clutch 94, so that the feed cam 33 is connected in driving relation with the shaft 89 and the feed carriage 22 is advancing. In this position of the parts the stop cam 102 is held against rotation, and the indexing mechanism is inactive.

As soon as the stop cam 102 is released, however, the earn 134 rotates with it, forcing the plunger 136 down, and operating lever 95 to open clutch 94. The feed cam 33 and main feed carriage are thus brought to rest. The plunger 136 is held by the cam 134 in this lower position until the shaft 103 has made a complete turn, and consequently, until the indexing operation has been completed, after which the roller 135 reenters the depression 138 and the plunger 136 rises and closes the clutch.

A brief description of the operation of the entire mechanism will now be given. The work 0 is clampedonto the arbor 15, with the arbor housing 13'properly adjusted upon the table 11. The clutch 94 is closed continuously across the work, each follow-- ing its individual curved path so as to form a side wall of the slot, and both operating to form the base of the slot. During each inward cutting stroke of each tool, its individual supporting carrier 46 or'46 is ad vanced along the carriage 22 to-efl'ect cutting engagement of the tool against the work, and during each outward or return stroke, its carrier is retracted to permit the tool to clear the work. The feed carriage 22 continues to advance, under the action of the cam 33 and lever 24, until the shoe 36 on the lever passes over the shoulder 43 on the cam. WVhen this occurs lever 24 swings in the opposite direction and the feed carriage is retracted. During this return stroke of the feed carriage, the plate 132 on the arm 133, carried thereby, strikes the-plate 131 and rocks the trip lever 127,

so that the stop cam 102 is released, in the manner hereinabove described, and shaft 103 rotates and drives the indexing mechanism.

The cam 134, rotating with shaft 103, forces the plunger 136 down, thereby rocking the lever 95 so as to open the clutch 94 in the manner hereinabove described.

Shaft 90 is thus upcoupled from shaft 89.

and the feed cam 33 and feed carriage 22 comes to rest. The cam 33 and feed carriage remain at rest until the shaft 103 and cam 134 has made a complete turn and the roller 135 on plunger 136 is reengaged within the depression 138 of cam 134. When this occurs the plunger 136 is again elevated and the clutch 94 closed so that the feed cam 33 is again actuated to again advance the feed carriage toward the work.

Each complete revolution of shaft 103 is transmitted through the gears 106, worm 21 and worm Wheel 19 to the arbor 15, to properly index the work. The angle through which the arbor 15, and consequently the work, is rotated may be varied by changing the gears 106 in a well known manner. As above explained shaft 103 is brought to rest at the end of each complete rotation thereof by engagement of the plunger 109 with the shoulder 112 on the stop cam 102, the plung- 7 ever, the consequent rotation of shaft 103 causes the cam 134 to immediately depress the plunger 136 and thereby open the clutch so as to bring the feed cam 33 and feed carri'ageto rest. It is thus impossible to ad- Vance the feed carriage toward the work during the operation of the indexing mechamsm.

In order to permit adjustment of the arbor' housing 13 toward or from' the tools, to accommodate the machine to work of different sizes, without interfering with the operation of the @machine, the shaft 96 is splined to the disk 99, so as to permit lengthwise movement thereof with the casing 104 during such adjustment of the arbor housing. The cam 134 is also of cylindrical form and of sufficient length to maintain contact bodiment of the invention hereinabove specifically described without departing from or sacrificing the advantages of the invention defined in the appended claims.

I claim 1. Ina machine tool the combination of a work support, a pair of oppositely arranged cutting tools for forming the opposite walls of a slot, separate slides for said tools, separate guides for said slides disposed end to end, and means for reciprocating said slides to thereby reciprocate said tools through the same slot and to effect a cutting stroke in each direction of reciprocation.

2. Ina machinetool the combination of a work support, a pair of oppositely arranged cutting tools for forming the opposite walls of a slot, separate slides for said tools, separate curved guides for said slides-disposed end to end, and means for reciprocating said slides to thereby reciprocate said tools through the same slot and to effect a cutting stroke ineach direction of reciprocation.

3. In a machine tool the combination of a work support, apair of oppositely arranged cutting tools for forming the opposite walls of a slot, separate siides'for said tools, separate curvedguides for said slides arranged end to end, a separate carrier for each guide, means for reciprocating said slides to reciprocate said tools through the slot and to effect a cutting stroke in each direction of reciprocation, and means for reciprocating said carriers.

4. In a machine tool the combination of a work support, a pair of oppositely ar-- ranged cutting tools for forming the -opposite walls of a slot, separate slides for said tools, separate guides for said slides arranged end to end, a separate carrier for each =guide,means for reciprocating said slides to reciprocate said tools through the slot an d to eifect a cutting stroke in each direction of reciprocation, and means for re cip'rocating said carriers.

arate guides for. said slides arranged end to' end, a carrier for each guide, amovable support for both carriers, means for reclprocating said slides to reciprocate said tools through the slot and'to effect a cutting stroke in each direction of reciprocation, means for reciprocating said carriers in timed relation with said slide reciprocating means, and means for advancing and retracting said carrier support toward and from said work support.

6. In a machine tool or the like the combination of a work support, a tool support,

feed mechanism for advancing one of said supports relative to the other, indexing mechanism, means controlled by the movable support for operating said indexing mechanism and means controlled by said indexing mechanism for preventing operation of said feed mechanism while said indexing mechanism is active.

7 In a machine tool or the like the com bination of a work support, a tool support, feed mechanism for advancing one of said supports relative to the other, indexing mechanism, and means responsive to action of said indexing mechanism for rendering said feed mechamsm inactive.

8. In a machlne tool or the like the combination of a work support, a tool support, feed mechanism for advancing and returning one of said supports relative to the other, indexing mechanism, and a trip mechanism controlled by the return stroke of the movable support for rendering said indexing mechanism active.

9. In a machine tool or the like the combination of a work support, a tool support, feed mechanism for advancing and returning one of said supports relative to the other, and a trip mechanism controlled by thereturn stroke of said movable support for rendering said feed mechanism inactive.

10. In a machine tool or the like the combinationof a work support, a tool support,

1 feed mechanism, for advancing and returning one of said supports relative to the other, indexing mechanism, means controlled by the return stroke of said movable member for rendering said feed mechanism inactive, and means controlled by said indexing mechanism for rendering said feed mechanism active.

11. In a machine'tool or the like the combination of'a work support, a tool support,

feed mechanism for efiecting a relative advance between said supports, indexing mechanism, a power driven shaft, a frictional controlled by said feed mechanism for releasing said stop to thereby render said indexing mechanism active.

12. In a machine tool or the like the combination of a work support, a tool support, feed mechanism for effecting a relative advance between said supports, indexing mechanism, a power driven shaft, a frictional driving connection between said shaft and indexing mechanism, a stop for rendering said driving connection ineffective to there by lock said indexing mechanism, means controlled by said feed mechanismfor releasing said stop to thereby render said in dexing mechanism active, driving connections between said shaft and feed mechanism, and means controlled by said indexing mechanism for controlling said last named connections.

13. In a machine tool or the like the combination of a work support, a tool support, feed mechanism for effecting a relative ad vance between said supports indexing mechanism for one of said supports, a power driven shaft, a clutch between said shaft and feed mechanism, and means controlled by said indexing mechanism for controlling said clutch.

14. In a machine tool or the like the combination of a work support, a tool support, feed mechanism for advancing and retract ing one of said supports relative to the other, indexing mechanism, yieldable driving means for said indexing mechanism, a positive stop for said indexing mechanism operable to restrain the same against movement by said driving means, and means controlled by movement of the movable support for controlling said stop.

In witness whereof, I hereunto subscribe my name this 24th day of February, 1926.

HERMAN E. FRENTZEL. 

